Matchlock

Actually, the match wasn't really a match, it was a piece of rope or twine. The gunner (the first matchlocks were basically light cannon, supported by a forked stick, it was so heavy) would touch the burning end of the rope, also called a "punk" to a hole in the base of the gun, igniting the powder and firing the round.

This method eventually became more refined, with a small lever holding the end of the punk in a clamp performing the firing action. This enabled the gunner to better maintain a sight picture, as he no longer needed to watch the end of the rope to make sure it touched the hole. The lever was joined at a pivot point on the stock near the rear hand of the shooter. This eventually became the lockmechanism, with a trigger releasing a spring-loaded lever (the lever "locked" into place, get it?) This enabled the weapon to fire at a more predictable interval from the time the gunner pulled the lever.

This spring-loaded lever action is the precursor to the flintlock, as stronger springs and more consistent mechanisms enabled the weapon to strike a spark instead of having to carry a constant flame. A comparison could be made to a gas stove with a pilot light and one with a spark igniter, with the latter being much safer.

The reasons for creating the fire each time as opposed to carrying it constantly are multifold. First, if you make the fire each time, it will be there every time you need it. A matchlock operator had to stand with the rope in his hand, spinning it to keep it alight while he waited to use it. Second, the gunner had to keep adjusting the rope in the holder during fire, as it burned down. This reduced firing time and reliability. Third, the weapon still had to be reloaded while you are spinning your rope and adjusting it in the little clamp in the lever. As this loading involved pouring loose black powder into the gun, any chance contact between the burning punk and the power would result in your enemies having one less guy to kill.

This was exacerbated by your colleagues spinning their ropes all around you in the heat of battle, so even if you avoided touching your punk and powder together, an errant rope end could swing by and touch off your powder while you were busy adjusting your punk, pouring your powder, and ramming your patch and ball.